1. Technical Field
The present invention relates to a method for forming a complex between an analyte or an analogue thereof in a sample, and a substance formable a complex with said analyte or analogue thereof (hereinafter, abbreviated as a complex forming substance or CFS), a method for separating a complex formed, and a CFS or an analogue not involved in formation of said complex, along with a method for measuring an analyte in a sample, based on the amount of a complex separated, or the amount of a CFS or an analogue not involved in formation of a complex.
2. Background Art
Analysis of an analyte in a sample usually requires mixing a plurality of solutions such as a sample and various reagent solutions (for example, a reagent solution including an antibody to an analyte, a reagent solution containing a labeling substance, and the like) etc., and subjecting an analyte in a sample and a reactant in a reagent solution (an antibody to an analyte or a labeling substance, and the like) to a reaction.
In Micro Total Analysis System (μ-TAS) using micro fluidics device, wherein, technology thereof has recently been developing and various researches thereon have been made, a method for mixing these plurality of solutions in advance and subjecting to a reaction outside a capillary (channel), then introducing the mixed solution into a capillary (channel), or a method for simultaneously introducing a plurality of solutions into a mixing capillary (channel) to carry out mixing and reaction (Patent Literature 1) has been known.
However, in the former method, a sample or a reagent solution in the amount of micro litter (μl) order is required for mixing in advance, which loses merit of μ-TAS, namely possibility of micro analysis of a sample or a reagent solution in the amount of from nano litter (nl) to pico litter (pl) order. In addition, in the latter method, laminar flow generating in a capillary in introduction makes mixing of a plurality of solutions difficult, resulting in requirement to depend on molecular diffusion, which poses such a problem as, in the case of mixing a plurality of solutions with different molecular weight or viscosity, the variation of complete mixing time of these solutions due to variation of diffusion coefficient, or variation in viscosity ratio of solutions to be mixed varies volume ratio of a plurality of solutions to be introduced in a channel, which results in variation of mixing ratio depending on kinds of solutions to be mixed, which poses a problem of making mixing in constant mixing ratio impossible.
In addition, as a method other than the above, there are methods disclosed in Bao, J. M, Regnier, F. E, J. Chromatogr. 1992, 608, 217-224 (Non-Patent Literature 1) or JP-A-10-512371 (Patent Literature 2).
In these methods, in a capillary for analysis, a solution including a molecule with higher electrophoretic mobility is arranged at the backward of a solution containing a molecule with lower electrophoretic mobility, so that a molecule with higher electrophoretic mobility overtakes a molecule with lower electrophoretic mobility, by application of electric field, by which a reaction between these molecules themselves is carried out. These methods make possible molecular mixing uniformly and in a short time compared with conventional mixing methods depending on molecular diffusion.
However, these methods are not satisfactory in reaction efficiency, and countermeasures to ensure sufficient reaction efficiency is required to detect an analyte in a sample in high sensitivity, for example, to increase concentration of molecules to be fed to a reaction, or to longer reaction time by delaying molecular movement rate by electrophoresis.
Patent Literature 1: JP-A-2005-31070
Patent Literature 2: JP-A-10-512371
Non-Patent Literature 1: Bao, J. M, Regnier, F. E, J. Chromatogr. 1992, 608, 217-224